Just snap a picture of it, and attach the image to an email by tapping and holding within the message body and selecting "Insert Photo or Video." Next, locate the image, select "Choose," then press and hold on it. From the pop-up menu, pick "Markup." You can then draw circles or lines and add a text box, or even append your signature to the image before emailing it. You don't get the most complete set of image markup tools in iOS 9, but they are useful for quickly annotating screen shots, photos, Web pages and other images.
A stylus, such as the new Jot Dash ($50) or Apple's upcoming Pencil ($99; for iPad Pro only), may come in handy if you plan to do a lot of image markup, especially on a smaller-screen device like an iPhone.
Sign up for CIO Asia eNewsletters.